Facebook has been hit with legal challenge from a convicted drug user who
claims he is entitled to 84pc of the social networking giant.

Paul Ceglia, who says he is a business partner of the world’s youngest billionaire, Mark Zuckerberg, is attempting to file a lawsuit for the “sweat equity” he says he expended while helping to set up Facebook.

Ceglia claims he hired Zuckerberg in 2003, when the latter was an 18-year-old Harvard undergraduate, to work on coding for a site called Streetfax. Zuckerberg was allegedly paid $1,000 before being put to work on a project called "The Face Book".

Orin Snyder, a lawyer for Facebook, has dismissed the claims. “This is a lawsuit brought by a convicted felon and we look forward to defending it in court," he said.

Ceglia was convicted of possessing halucinogenic mushrooms in 1997.

The lawsuit follows a failed appeal by Cameron and Tyle Winklevoss, who claimed their $65m legal settlement in 2008 was too low. The twins maintain that the idea for Facebook was stolen from them by Zuckerberg, who denies the claims.